Q: I don’t think we should build any reactors until we have a repository for the waste ready to go…

A: I understand this position (don’t make waste until you have the ability to dispose of it properly).But the major problem we face is that we are using our atmosphere as our primary waste repository for the products of fossil fuel combustion. We have a strong scientific and technical consensus that deep geologic disposal can provide acceptable long-term isolation of nuclear wastes, and we have two countries now that have successfully developed and are building repositories for commercial spent fuel (France and Sweden).

We also have no plausible approaches to remove CO2 waste from the atmosphere once it is put there, except for some scary geoengineering ideas (such as fertilizing the oceans). Future generations are likely to be much more angry about the CO2 we’re generating now, than the nuclear waste.

Members of the UC Berkeley Department of Nuclear Engineering participated in the Reddit.com Science AMA Series, responding to a large number of largely hostile questions. Lots of variations of “Can I still eat fish from the contaminated Pacific”. As typical with these AMA sessions the signal to noise ratio is low due to the uninformed questions and irrelevant branched threads of discussion by people who are more interested in politics. I “mined” the 1,447 comments for what I thought were fragments worth archiving.

I guess I’ll start things off. What type of reactors should we be building? I know a big deal a few years ago was made about liquid flouride thorium reactors. Is that the way of the future, or are there superior alternatives?

I do not think that we have the basis to determine or select the best coolant or fuel type to use in future reactors. But there are some attributes which we do need to make sure are used in future reactors.

The first is to use passive safety systems, which do not require electrical power or external cooling sources to function to remove decay heat after reactors shut down, as is the case with the AP-1000 and ESBWR designs, and with all of the light water reactor SMRs now being developed in the U.S.

The benefits of passive safety go well beyond the significant reduction in the number of systems and components needed in reactors and the reduced maintenance requirements. Passive safety systems also greatly simplify the physical protection of reactors, because passive equipment does not require routine inspections the way pumps and motors do, and thus can be placed in locations that are difficult to gain access to rapidly.

The second is to further increase the use of modular fabrication and construction methods in nuclear plants, in particular to use steel-plate/concrete composite construction methods that are quite similar to those developed for modern ship construction. The AP-1000 is the most advanced design in the use of this type of modularization, and the ability to use computer aided manufacturing in the fabrication of these modules makes the manufacturing infrastructure much more flexible. In the longer term, one should be able to design a new reactor building, transfer the design to a module factory over the internet, and have the modules show up at a construction site, so the buildings are, in essence, 3-D printed.

The final attribute that will be important for new reactors will be to make them smaller, and to develop a regulatory framework and business models that work for multi-module power plants. While there will likely always be a market for large reactors, creating an ecosystem that includes customers for smaller reactors (inland locations served only by rail, installations needing reliable power even if fuel supplies are interrupted, mature electricity markets that need to add new capacity in small increments).

On thorium, a question:

Hello! What do you think is the most important advantage that thorium has over uranium as a “fuel?”

The thorium fuel cycle has clearly attractive features, if it can be developed successfully. I think that most of the skepticism about thorium emerges from questions about the path to develop the necessary reactor and fuel cycle technology, versus open fuel cycles (uranium from seawater) and closed, fast-spectrum uranium cycles.

The most attractive element of the thorium fuel cycle is the ability to operate sustainably using thermal-spectrum neutrons. This allows the design of reactor core structures that use high-temperature ceramic materials like graphite, which have substantial thermal inertia and cannot melt. Because these ceramic materials also provide significant moderation, it is difficult to use them in fast-spectrum reactors and thus the most plausible fast-spectrum reactor designs need to use metallic structural materials in their cores.

So thorium reactors are compatible with higher intrinsic safety (cores which do not suffer structural damage even if greatly overheated) and that can deliver heat at higher temperature, which enables more efficient and flexible power conversion.

Molten fluoride salts are compatible with these high-temperature structural materials, and given their very high boiling temperatures make excellent, low pressure heat transfer fluids. In the near term, the largest benefits in using fluoride salts come from the low pressure and high temperature heat they can produce. This can be achieved with solid fuel, which is simpler to work with and to obtain regulatory approvals.

But molten salt technologies also have significant challenges. One of the most important is managing the much larger amounts of tritium that these reactors produce, compared to light water cooled reactors (the quantities are closer to what heavy-water reactors, such as the CANDU, produce, but methods to control and recovery of tritium are much different for molten salts than for heavy water, and key elements remain to be demonstrated).

To repeat a critical point “…largest benefits in using fluoride salts come from the low pressure and high temperature heat they can produce. This can be achieved with solid fuel…”. This summarizes why Prof. Peterson’s lab is focused upon developing the PB-AHTR design, which will also prove out many materials and technologies required subsequently to implement the more challenging Liquid Fuel molten salt reactor concept (such as LFTR).

Regarding waste: Prof. Peterson was a member of Obama’s Blue Ribbon Commission on America’s Nuclear Future. I consider him one of the best-informed sources regarding Spent Nuclear Fuel (SNF) which the anti-nuclear lobby calls Nuclear Waste. It is not “waste” it is an extremely valuable source of carbon-free energy.

A: …Finland and Sweden have successfully sited and are building deep geologic repositories in granite, and France is very far along in developing its geologic repository in clay. The U.S. nuclear waste program is currently stopped and is in a state of disarray…

There are a wide range of opinions as water reactors (LWRs) is substantially more expensive than making new fuel from uranium, even if the plutonium is free. This is primarily because the plutonium must be handled as an oxide powder to make LWR fuel, and oxide powder is the most hazardous and difficult form to handle plutonium in. All of the Generation IV reactor technologies can use fuel forms that do not involve handling plutonium and minor actinides in the form of powders and that are much easier to fabricate using recycled material (e.g., metal, molten salt, sol-gel particles in either coated particle or vibropacked fuel forms).

In my personal opinion, the most sensible thing to do in the near term is to prioritize U.S. defense wastes for geologic disposal, and to use a combination of consolidated and on-site interim storage for most or all commercial spent fuel. Implementation of the Blue Ribbon Commission’s major recommendations, which include development of consolidated interim storage that would initially be prioritized to store fuel from shut down reactors, would put the U.S. on this path.

By using geologic disposal primarily for defense wastes first, and using primarily dry cask interim storage for commercial spent fuel, this will give a couple of decades for nuclear reactor technology to evolve further, and by then we will be in a better position to determine whether commercial spent fuel is a waste or a resource.

There are a number of factors which make innovation difficult in improving nuclear reactor technology, in particular the long operating life of nuclear power plants and their very large capital costs, which dissuade innovation. The trend toward designing larger and larger water-cooled reactors has increased these disincentives.

Given their lower capital cost and shorter construction times, innovation is much easier in small reactors. There will remain a role for large reactors, just as dinosaurs existed for millions of years alongside the new mammal species, but currently some of the most important policy issues for nuclear power involve creating an ecosystem where small reactors find customers. Smaller reactors, produced in larger numbers with most of the fabrication occurring in factories, would also use specialized manufacturing and skilled labor more efficiently. Imagine factories as being similar to airplanes, and the ability to keep more seats filled being really important to having low per-seat prices…

FHR (Fluoride Salt Cooled High Temperature Reactor), Where to take technical risk?

I will answer this question first indirectly, and then more directly.

A key question for innovation in developing new nuclear energy technology is where to take technical risk. SpaceX provides a good example of a highly successful risk management strategy. They focused on developing a highly reliable, relatively small rocket engine, that they tested in the Falcon 1, which uses an ancient rather than innovative fuel combination, kerosene and liquid oxygen. On the other hand, they chose to use aluminum-lithium alloy with friction stir welding for their fuel tanks, which is at the cutting edge of current technology. They have then used the approach of ganging together large numbers of these engines to create the Falcon 9, which is now successfully delivering cargo to the International Space Station.

Currently the most important barrier to deploying nuclear power is not the cost of the fuel, but instead is the capital cost of the plants, the need to assure that they can run with high reliability (which for current large reactor designs creates strong disincentives to innovate), and the relatively low electricity revenues one receives for producing base load power, particularly today in the U.S.

The primary reason that UCB, MIT, and UW, and the Chinese Academy of Sciences, are working on solid fuel, salt cooled reactor technology is because we have the ability to fabricate these fuels, and the technical difficulty of using molten salts is significantly lower when they do not have the very high activity levels associated with fluid fuels. The experience gained with component design, operation, and maintenance with clean salts makes it much easier to consider the subsequent use of liquid fuels, while gaining several key advantages from the ability to operate reactors at low pressure and deliver heat at higher temperature.

Q: Can I also ask what you think the safest way to transport the waste is?**

A: Per Peterson:There is a long record of safe transportation of nuclear waste, including spent fuel, world wide. The containers used to transport nuclear wastes are substantially more robust than those used to transport hazardous chemicals and fuels, which is why transportation accidents with chemicals generate significantly more risk.

This said, the transportation of nuclear wastes requires effective regulation, controls, and emergency response capabilities to be in place. The transportation system for the Waste Isolation Pilot Plant in New Mexico has logged over 12 million miles of safe transport, with none of the accidents involving the transportation trucks causing any release of radioactive materials.

One reason it is important to restore WIPP to service (it had an accident involving the release of radioactive material underground in late February, which had minimal surface consequence because the engineered safety systems to filter exhaust air were activated) is because the WIPP transportation system has developed a large base of practical experience and skilled personnel at the state and local levels who are familiar with how to manage nuclear waste transport. This provides a strong foundation for establishing a broader transportation system for commercial spent fuel and defense high level wastes in the future.

Actually I work for this program and this is an understatement. Not only have there never been any accidents that caused a release of nuclear material, there have never been any accidents with a truck loaded with waste containers, ever. They’ve happened while empty, but never otherwise.

Per Peterson discussed the unpriced carbon emissions externality. Which I would say is effectively a tax on nuclear because nuclear produces nearly zero carbon energy in competition with coal and gas which do not pay their carbon externality costs. Per raised a very important issue: how the NRC gatekeeping sets up a strong incentive to free-ride on NRC rulings.

But there is another important market failure that affects nuclear energy and is not widely recognized, which is the fact that industry cannot get patents for decisions that the U.S. Nuclear Regulatory Commission makes. For example, there are major regulatory questions that will affect the cost and commercial competitiveness of multi-module SMR plants, such as how many staff will be required in their control rooms. Once the first SMR vendor invests and takes the risk to perform licensing, all other vendors can free-ride on the resulting USNRC decision. This is the principal reason that government subsidies to encourage first movers, such as cost sharing or agreements to purchase power or other services (e.g., irradiation) make societal sense.

Is this being discussed in the USgov? I’ve never seen a word about it. This is another example of the sub-optimal result we get from wasting billions on energy-farming production subsidies, while rationing a few millions for nuclear R&D. Even America has very limited funds – and needs to spend them very carefully.

Geoff wrote a pithy comment on the 2012 Nature article on advanced nuclear.

The characterisation of India's 1974 bomb as being “from reactor fuel” inviting “rampant nuclear-weapons proliferation” is unsupported by consequent events. There has not been rampant nuclear weapons proliferation. The invitation was clearly declined. John Mueller's “Atomic Obsession” goes into substantial detail in its explanations of why this hasn't happened, but the brute fact is that it hasn't. The fact that something is technically possible says nothing about its likelihood and the world now faces real climate dangers while being hamstrung in the deployment of our most scalable energy system because of bizarre imaginings. Had the US and other countries followed France and not been scared by these imaginings, they'd all be producing electricity for 90 grams of CO2/kWh instead of the current global average of 500 grams CO2/kWh and the world would be a much, much safer place with a far more manageable climate problem. We must not let over active imaginations stand in the way of a massive deployment of clean nuclear energy.

We don’t have a technical nuclear waste problem, but we sure have a political problem. To demonstrate, I’ll repeat a few paragraphs from a June 2013 post:

Negligible risks/impacts

As someone who works in the area of dry fuel storage, I can tell you that the answer is pretty obvious. The risks of spent fuel storage are utterly negligible, compared to other risks that society routinely faces in general, and in particular, compared to the risks associated with alternative (fossil) power generation options. No credible scenario for a significant release from dry storage casks exists. Even terrorist attacks would have a minimal public health consequence.

Spent fuel pool risks are also quite low, and neither the 5-year cask requirement nor a repository would do much to reduce those (small) risks, since almost all the heat in spent fuel pools is from the fuel younger than 5 years. The theory of spent fuel pool cladding melt or fire (in the extremely unlikely, hypothetical event of pool drainage) is quite dubious in the first place, and it is being addressed at the few plants where it is thought to be a potential concern. Also of note is the fact that the spent fuel pools did NOT release any significant amount of radioactivity at Fukushima.

The fact is that nuclear waste is generated in a miniscule volume and, unlike the wastes from fossil plants and other industries, it has always been safely and fully contained, has never been released into the environment, and has never caused any harm. Further evaluation needed? In my view, the health/environmental impact evaluation for long-term onsite storage of used fuel could be adequately given in one sentence:

“The public health risks and environmental impacts of long term onsite storage of used nuclear fuel are clearly orders of magnitude less than those of the fossil fueled power generation that would otherwise be used in place of nuclear generation.”

It’s clear that shutting the industry down until a repository is built will result in fossil fuels being used for most of the replacement power. Even if new plant licensing and plant life extensions are suspended, for a long time, the result will eventually be some reduction in nuclear generation, and will result in some increase in fossil generation.

That was written by senior nuclear engineer Jim Hopf who just happens to be a specialist in this area. Nuclear engineers often refer to “waste” as SNF or Spent Nuclear Fuel. It is not actually spent, because in light water reactors less than 1% of the energy has been extracted in a the Jimmy Carter-mandated once-through fuel cycle. The remaining 99% is awaiting favorable politics to be turned into electricity in advanced reactors such as the IFR. So please do not bury the SNF (high value zero-carbon energy) where it will be difficult to retrieve.

Today I read some useful commentary on how the US got into this mess. I was reading the captioned dialog on Our Energy Policy, when I came to comments by an informed observer, Geoffrey Rothwell, who is Principal Economist, Nuclear Energy Agency of the Organization for Economic Cooperation and Development. That’s the NEA of the OECD. Geoffrey’s comments:

There are plenty of issues to discuss here, and it seems that the discussion is going off on tangents. For example, I believe that Elliot Taubman meant to say that it isn’t Department of Energy’s fault that Yucca Mountain was defunded. There is a general assumption that the US Government is the Administrative Branch and does not include Congress and the Judiciary; hence, the confusion. Yucca Mountain was on track until the Environmental Protection (?) Agency determined that the design basis of 10,000 years wasn’t long enough to protect future human species from the present generation’s nuclear spent fuel. Thus, it increased the required design basis to 1,000,000 years. While I can imagine 10,000 years into the future (because we can look back at civilized humans over the last 10,000 years), I cannot (and I daresay no one can) design a facility to function as designed for a million years. This slowed down DOE’s license application to such an extent that the NRC was unable to license the design before the Obama-Reid-Pelosi administration took office in January 2009.

What was the implication? The Nuclear Waste Policy Act states in Section 148(d) of the Nuclear Waste Policy Act, PL 97-425, 42 USC 10168: “(d) LICENSING CONDITIONS–Any license issued by the Commission for a monitored retrievable storage facility under this section shall provide that– (1) construction of such facility may not begin until the Commission has issued a license for the construction of a repository under section 115(d); (2) construction of such facility or acceptance of spent nuclear fuel or high-level radioactive waste shall be prohibited during such time as the repository license is revoked by the Commission or construction of the repository ceases;…” Therefore, without a license for a repository, no interim storage facility could be contemplated by the DOE; hence the waste confidence issue appeared. All Congress must do is strike Section 148(d), but that implies that Congress could do something. I don’t believe that Congress will do anything. If one looks at all previous legislation related to nuclear power policy since the Three Mile Island accident, it requires at least 3 sessions of Congress to act and then Congress will only pass such legislation after the elections, i.e., in lame duck sessions (where nuclear power policy cannot be used by non-incumbent candidates as a political weapon). Therefore, while Senate Bill 1240 is a good start, as long as Harry Reid is in power, nothing will happen. Is there a House counterpart? If not, why not? (Because House leadership wants to see Yucca Mountain licensed so as to avoid throwing $10B in Yucca Mountain characterization down a hole, literally).

Why isn’t reprocessing a solution? Unfortunately, when Congress passed the legislation in 1986 limiting characterization of reprocessing sites to Yucca Mountain (because more powerful members of Congress didn’t want the repository anywhere near their backyards (note, however, there is an operating repository in New Mexico at the Waste Isolation Pilot Project, WIPP), the size of Yucca Mountain was limited to 80,000 metric tons of heavy metal (spent uranium fuel). But 80,000 MTHM doesn’t really have anything to do with the carrying capacity of a repository. The carrying capacity of a repository is limited by the ability of the surrounding geology to dissipate heat over the life of the facility. Once the repository is filled, radioactive decay increases the heat in the repository for hundreds of years before cooling begins. Reprocessing reduces the volume and tonnage of the waste, but doesn’t really change the heat load unless the various radio-isotopes can be separated into separate waste streams. This requires new reprocessing technologies and, unfortunately, there is little money to develop these technologies, which require international cooperation and development (every country with spent nuclear fuel is better off with more effectively reprocessing technologies, but no one country can afford to develop them).

On the other hand, the amount of waste that we are discussing is countable. What is uncountable is the equivalent amount of carbon dioxide. Each gigawatt-year of nuclear electricity produces approximately 20 tons of waste (note 20 tons x 40 years x 100 reactors = 80,000 MTHM: Dave, will you check my math?). Given the weight of these 20 tons, the volume is one-third the size of a reactor core: a countable number. One gigawatt-year of coal electricity produces 1,000,000 tons of CO2 (note: 1M tons x 40 years x 100 gigawatts = 4 billion tons of CO2; there are approximately 5 milligrams of CO2 in 12oz can of soda; therefore, we would need to bury 200,000 cans of soda to sequester 1 ton of CO2, i.e., 800 trillion cans of soda; Dave, please check my math). I exaggerate to make the point that Carbon Capture and Storage is a myth and the Waste Isolation Pilot Project is a reality. Finally, climate change is a reality, Hurricane Sandies don’t care whether you believe in climate change: they will flood the New York subway whether you believe in climate change or not. The issue is whether it is easier to manage spent nuclear fuel or CO2. What do you think?

Regarding the quantity of SNF, Geoffrey says it is “countable”. Another adjective is “minuscule”.

Conca: WIPP stores defense-related radioactive waste, called transuranic waste. It has to be remotely handled, shielded, the whole bit. We’ve been doing this for 11 years now.

There are no unknowns. We know exactly how much [a deep geologic repository] costs. We know exactly how to do it. It’s incredibly safe. The United States has a deep geologic nuclear repository that’s half-full and nobody even knows about it.

Q: What have been the findings of the Carlsbad Environmental Monitoring and Research Center?

Conca: We have a 15-year record of the environment from before WIPP opened to the present. CEMRC has been operating since 1996 and WIPP since 1999. There’s been no change [in radioactivity at the site].

There’s a secure solution to America’s energy problem buried under booming Carlsbad, N.M. If only Washington would get out of the way.

French and US polls that I’ve read consistently show that people who live near nuclear power stations want to have more nuclear, not less. That perspective is almost impossible to find in the usual sensational media coverage. But this recent Forbes article is different. Carlsbad New Mexico is the site of the Waste Isolation Pilot Plant (WIPP ).

(…) Since opening in 1999, WIPP has operated so smoothly and safely that Carlsbad is lobbying the feds to ­expand the project to take the nuclear mother lode: 160,000 more tons of the worst high-level nuclear waste in the country

(…) Carlsbad has a different take. “It’s really a labor of love,” says Forrest. “We’ve proven that nuclear waste can be disposed of in a safe, reliable way.”

This attitude—“Yes in my backyard,” if you will—has brought near permanent prosperity to this isolated spot that until recently had no endemic economic engine. Unemployment sits at 3.8%, versus 6.5% statewide and 8.5% nationally. And thanks to this project—euphemistically known as the Waste Isolation Pilot Plant, or WIPP—New Mexico has received more than $300 million in federal highway funds in the past decade, $100 million of which has gone into the roads around Carlsbad. WIPP is the nation’s only permanent, deep geologic repository for nuclear waste. The roads have to be good for the two dozen trucks a week hauling in radioactive drums brimming with the plutonium-laden detritus of America’s nuclear weapons production.

As recommended by the Obama administration’s blue ribbon commission, community involvement is essential to the successful siting and operation of a spent fuel storage facility. A similar story is found in the Swedish town of Östhammar a town of 22,000 inhabitants a two-hour drive north of Stockholm. Spiegel May 19, 2011 Why One Swedish Town Welcomes a Waste Dump. The towns of Östhammar and Oskarshamn competed for the new storage facility:

(…) For years, local officials were worried that another town with a nuclear power plant — Oskarshamn, which is 465 kilometers away and was also vying to be the site of the repository — would end up winning the contest. The two towns decided to make a deal. The company building the repository, Svensk Kärnbränslehantering (SKB), would provide two billion Swedish krona, or about €223 million ($312 million), of which the runner-up would receive 75 percent and the winner only 25 percent.

Some might say it was an attractive incentive for one of the towns to step on the brakes and come in second place.

The decision was made on a rainy summer day in 2009. Edelsvärd remembers the day very clearly. Östhammar town officials were sitting at the town hall, watching a live broadcast of the showdown in Stockholm. When the name of their community appeared on the screen, Edelsvärd says that “people weren’t cheering the way they would at a football match, but you could sense the feeling of elation in the room. It was a very Swedish way of expressing joy.”

Please remember that what the media and Greenpeace call “nuclear waste” is actually incredibly valuable fuel for power generation. E.g., in the case of England, the UK DECC chief scientist David MacKay supported estimates that all of England’s electrical needs can be supplied for 500 years by burning the existing UK “waste”. This is in the context of Duncan Clark’s article on deployment of fast reactors such as the GE Hitachi PRISM being proposed to burn the UK “waste plutonium”.

(…) According to figures calculated for the Guardian by the American writer and fast reactor advocate Tom Blees, this alternative approach could – given a large enough number of reactors – produce enough low-carbon electricity from Britain’s waste stockpile to supply the UK at current rates of demand for more than 500 years.

MacKay confirmed this figure. “As an upper bound on what you could get from those resources in fast reactors I think it’s a very reasonable estimate. In reality you’d get all kinds of issues so you wouldn’t achieve the upper bound but I still think it’s a reasonable starting point.”

(…) Reprocessing has great potential value for the United States. Using it along with breeder reactors would recover 90 percent of the original energy that remains in the fuel after one use in a reactor. And it would extend uranium resources for hundreds of years and reduce by at least 50 percent the amount of long-lived nuclear waste that would need to be stored in a deep-geologic repository. Additionally, the heat and toxicity of such waste would be reduced, enabling the United States to store all of the long-lived waste from power reactors and the weapons program in a single repository instead of having to find sites and pay for the construction of multiple repositories.

Such a reprocessing plant could be located at the Savannah River Site. Both South Carolina senators — Lindsey Graham and Jim DeMint — are outspoken supporters of nuclear power who favor the idea of building a used-fuel reprocessing plant at this nuclear installation.

Another facility to convert surplus weapons plutonium into MOX fuel for power reactors is under construction at the Savannah River Site, providing thousands of jobs and revenue for South Carolina.

How ironic that Congress has approved the processing of weapons plutonium into MOX fuel for commercial electricity production but has yet to do the same for reprocessing used fuel stored at nuclear power plants. This contradictory policy is absurd.

Pew publishes a useful fact sheet on nuclear power. The most recent version is August 2009. They pack a lot of facts in a short document, ranging from costs to the reactor design generations to environmental benefits to policy options to help promote nuclear power. I checked their “facts” fairly carefully, finding no errors.

(…) The report also strongly supports the present US government policy of providing loan guarantees for the first several new nuclear plants to be built under newly revised licensing rules. Positive experience with “first-mover” plants—the first of these new US plants built after the current long hiatus—could reduce or eliminate financing premiums for nuclear-plant construction. Once those premiums are eliminated, Forsberg says, “we think nuclear power is economically competitive” with coal power, currently the cheapest option for utilities.

The central conclusion of this just-released MIT study [PDF of the report summary] will not surprise regular Seekerblog readers: there is plenty of uranium and even more thorium, so there is no resource constraint on the rapid growth of nuclear power. I recommend reading the summary report carefully (the complete report chapters aren’t yet published on the web). For an overview, the MIT Energy Initiative press release is useful:

(…) Ernest J. Moniz, director of the MIT Energy Initiative and co-chair of the new study, says the report’s conclusion that uranium supplies will not limit growth of the industry runs contrary to the view that had prevailed for decades—one that guided decisions about which technologies were viable. “The failure to understand the extent of the uranium resource was a very big deal” for determining which fuel cycles were developed and the schedule of their development, he says.

The study concludes that a uranium-initiated breeder design with a unity conversion ratio of 1.0 is likely to be superior to higher-conversion-ratio designs (ratios of 1.2 to 1.3). That’s one of several new concepts for me:

The new study suggests an alternative: an enriched uranium-initiated breeder reactor in which additional natural or depleted (that is, a remnant of the enrichment process) uranium is added to the reactor core at the same rate nuclear materials are consumed. No excess nuclear materials are produced. This is a much simpler and more efficient self-sustaining fuel cycle.

I believe that the new MIT study is a “big deal” — it provides high-credibility backing to almost every nuclear fuel cycle concept that we have been proposing (such as preserving the enormous value of “waste” for future use as fuel cycle feedstock). Our job now is to motivate the politicians to adopt and implement the conclusions.

PS – I’m keen for Appendix A to be released “Thorium Fuel Cycle Options”.

One presentation caught my eye, by Dr. Clifford Singer of Univ. of Illinois. Excerpts from the summary emphasize the incentives — which seem to totally absent from all the existing law and regulation. Ensure there is competition among several states for storage operations:

Obtaining the cooperation of localities and states on siting spent nuclear fuel management facilities requires more than building trust with local communities. States having an appropriate site will view it as a valuable energy systems asset and will want financial compensation not at the level of a few percent, but measured in tenths of the cost of the entire project. If siting is really to be voluntary, it is important not to put a single state in a monopoly position of having the only licensed site. To do so will generate tension with the federal government over the level of financial benefit to the host state and within the host state over whether the final arrangement is equitable. There must be a sensible mechanism for compensating host states and a process that leads to more than one site being licensed and ready for use.

(…) Use of the Framework: Congress should set the maximum allowed Permanent Fund charges high enough to make hosting spent fuel management facilities something that several states desire rather than wish to avoid. A short list of geological repository sites in at least six states should lead to a competition to be amongst two or preferably three chosen for licensing. It is economically optimal to age spent fuel intact over a few of the c. 30 year half lives of its most intense fission product heat generators, before its final disposition. Thus, a similar number of spent fuel aging facilities should be licensed, some of which may be at repository sites. In this context spent fuel reprocessing will not be economically favorable for many decades, if ever. If a pilot scale reprocessing facility is nevertheless licensed, it should also be licensed as an indefinitely renewable aging facility, as no reprocessing facility anywhere has yet both operated as planned and removed all high-level radioactive materials from site.